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King vs two twin XL beds

Same footprint, different bed. Two twin XLs side by side are a split king.

Short answer: two twin XL mattresses (38 × 80 in each) side by side measure 76 × 80 in, the same as one king.[1 2 · Nov 11, 2026] That pair is called a split king.[1 · Nov 11, 2026] Pick two twin XLs if you want different firmness on each side or an adjustable base where each side moves on its own; pick one king if you'd rather have no seam down the middle.[1 · Nov 11, 2026]

Two parents, two young children and a golden retriever laugh together on a king bed in a bright bedroom with a beamed ceiling and big windows

Side by side

One kingTwo twin XLs (split king)
Size76 × 80 in[2 · Nov 11, 2026]2 × (38 × 80 in) = 76 × 80 in[1 · Nov 11, 2026]
Centimeters193 × 203 cm2 × (97 × 203 cm)
Fitted sheetsKingSplit king set: usually two twin XL fitted sheets and one king top sheet[1 · Nov 11, 2026]
ComforterKingKing, or separate smaller ones[1 · Nov 11, 2026]
Frame or baseKingStandard king frame or foundation, or a split king adjustable base[1 · Nov 11, 2026]
Seam in the middleNoYes; a king topper can cover it if you feel a dip[1 · Nov 11, 2026]

Choose two twin XLs (split king) if

Choose one king if

Room size is the same for both: one maker suggests about 12′ × 12′ for a king footprint.[3 · Nov 11, 2026] Compare a king with a California king on our king vs California king page, or see why twin XL is 5 in longer than a twin on twin vs twin XL. Sheet sizes for split kings are on sheet sizes.

Questions people ask

Do two twin XL beds make a king?

Yes. Two twin XL mattresses are 38 × 80 in each, so side by side they measure 76 × 80 in, the same as a standard king. This setup is called a split king.

Can I use king sheets on two twin XLs?

A king top sheet and comforter work. For fitted sheets, a split king set usually includes two twin XL fitted sheets so each mattress is covered on its own.

Will I feel the gap in a split king?

Lying flat, you usually shouldn't feel the gap between the two mattresses. If you do feel a dip, a king size topper can cover it.

Shopping now? See best mattress for a split king.

Sources: 1. Sleep Foundation, What is a split king bed?. 2. Sleep Foundation, Mattress sizes and dimensions guide. 3. Casper, Queen size bed dimensions: size, room fit, and how it compares. Checked Nov 11, 2026. Trademarks belong to their owners; figures are restated in our own words and tables, not reproduced.